Treatment for Tuberculosis
Treatment of active TB is complex and is becoming even more complex with the emergence of multidrug-resistant tuberculosis (MDR-TB) and HIV infection. Hospital admission is recommended for severe cases.
Standard therapy for pulmonary TB includes isoniazid and rifampin for 6 months along with pyrazidamide for the first 2 months (isoniazid and rifampin without pyrazidamide may be used for 9 months, if necessary). Treatment consists of three drugs that are effective against the organism.
If the incidence of drug-resistant TB in a community is greater than 4 percent, ethambutol or streptomycin is added until sensitivities are known. (All strains of bacteria are tested to determine the sensitivity to the antibiotics used.) Sputum should be negative after 3 months of therapy. If not, treatment is reevaluated.
If a patient is unable to tolerate isoniazid, or if isoniazid-resistant TB is present, rifampin, ethambutol, and pyrazidamide are usually used for 18 months. If rifampin-resistant TB is present, the regimen usually consists of isonizaid, ethambutol, and pyrazidamide for 18 months. If there is resistance to both isoniazid and rifampin, the disease is very difficult to treat.
In December 2012, the U.S. Food and Drug Administration (FDA) approved the first medication (bedaquiline [Sirturo]) to treat MDR-TB. Bedaquiline is used in combination with other drugs when alternative treatments are not available. This medication carries a Boxed Warning indicating that it may disrupt the heart's electrical activity and cause an abnormal and dangerous heart rhythm. Common side effects include headache, joint pain and nausea.
|Isoniazid||Hepatitis, peripheral neuropathy, central nervous system effects including seizures, psychosis, encephalopathy|
|Pyrazinamide||Arthralgia, hyperuricemia, hepatitis, photosensitivity, gastric irritation; contraindicated in pregnant patients|
|Rifampin||Drug interactions; gastric irritation; colitis; fever; puritis; anaphylaxis; thrombocytopenia; leukopenia; hemolytic anemia; elevated LFT (liver function test); flu-like symptoms; colors body fluids orange; may permanently discolor contact lenses|
|Streptomycin||Ototoxicity, paresthesia, dizziness, nausea, tinnitus, nephrotoxicity, peripheral neuropathy, allergic skin rash|
|Ethambutol||Optic neuritis, peripheral neuropathy, headache, rashes, arthralgias, hyperuricemia, anaphylaxis (rare)|
Standard Therapy for Extrapulmonary TB
Therapy for extrapulmonary TB uses the same drugs but may last longer. Steroid therapy may be useful in pericardial disease and is indicated in children with meningitis.
Surgery to Treat TB
With multidrug-resistant TB that does not respond to antibiotics, the infected portion(s) of the lung may be removed surgically. The prognosis for these patients is extremely poor. Tuberculosis empyema (pus in pleural fluid) may require chest-tube drainage of the pleural space.
TB Treatment during Pregnancy
Pregnant patients with TB usually receive isonizaid and rifampin with ethambutol. These drugs have not been found to be harmful to the fetus. Streptomycin is contraindicated because it causes deafness in the fetus. Pyrazinamide is also contraindicated in pregnant patients.
With good compliance, relapse is rare. Long term effects and complications due to scarring may occur. For those with extensive disease, the prognosis is poor.